Bar bending machine



Jan. 19, 1932. w 5, BROWN 1,841,784

BAR BENDING MACHINE Filed July 10, 1950 2 Sheets-Sheet l .719 if Z0 INVENTOR.

BY f777$es s wd/VLV/f M ATTORNEY Jan. 19, 1932. w. 5. BROWN BAR BENDING MACHINE Filed Ju1y'10, 1930 2 Sheets-$heet 2 INVENTOR BMW f Jfi}; A TTORNEY Patented Janl19, 1932 UNITED STATES PATENT OFFICE ,"W'IIILLIAlli S. BROWN, OF CARTI-IAGE, MISSOURI, ASSIGNOR TO LEGG-ETT AND PLATT 1 CORPORATION OF IIIISSOURI SEEING BED AND MANUFACTURING- COMPANY, CARTHAGE, MISSOURI, A

BAR BENDING MACHINE Applicationfiled July 10, 1930. Serial 110. 466,984.

S bends in a flat bar edgewise thereof.

One of the objects of my invention is to provide a bar bending machine of the kind described, having a cam bending member oscillative betweentwo fulcra with means by which the cam member may be oscillated continuously or at intervals by a rotary driving shaft.

A further object of my invention is to provide novel means for varying the range of oscillation, adjustably, whereby the machine is adapted for use with bars varying in width, or the bends in the, bar varied in the angles thereof. a o

A further object of my invention is the provision of novel means by which the bar which is being bent may be held, during the bending operation, from kinking.

" ble, notlustrate'the preferred Still anotherobject of my invention is to provide a bending machine of the kind described, which is simple, cheap, strong, duralikely to get out of order, which enables the bar to be bent, to be easily and quickly inserted intoproper position in the machine and to be easily and quickly witl drawn therefrom, after the bending operation,.without stopping the machine, if desired.

The novel features of my invention are hereinafter fully describedand claimed.

In the accompanying drawings, which ilembodiment of my invention, ,r

Fig. 1 is a top view of the machine, with the" cover removed.

Fig. 2 is a side elevation of the machine, looking at one side thereof, and showing the bar to be bent inserted ready to be bent.

Fig. 3 is a reduced elevation, partly broken away, looking at the sideof the machine opposite to that shown in Fig. 2.

Fig. l is an enlarged section on the line 4.& of Fig. 2.

Fig. 5 is an enlarged section on theline 55 of Fig.2. 7

Fig. 6 is an enlarged section on the line (l 6 of Fig. 2.

Fig. 7 is an enlarged section on the line (-1 of Flg. 3.

Fig. 8 is an elevation of the cam member,

the fulcra and parts connected therewith,

and showing the cam member after it has reached the limit of its bending movement, with a bar formed and held between the cams and the "fulcra.

Fig. 9 is an enlarged outside elevation of the cam member crank plate. V

Fig. 10 is a section on the line 10-10 of Fig. 9.

Fig. 11 is a reduced plan view of a bar which has had its end portions formed into S bends.

Similar reference characters designate similar parts in the diiferent views.

My machine provides a suitable support fortheparts comprising, as shown, a box 1 having a removable cover 2, and an L shaped bracket 3 fastened to one end of the box 1.

1 designates a fiat bar which is to bebent into S bends 5, shown inFigs. 8 and 11, the bar before bending being shown in Figs. 1, 2,4, 5 and 6.

For bending the bar into S bends there are provided two fulcra which, as shown, each comprises a roller 6 having at one end an annular peripheral flange 7, the roller being revoluble on a shouldered bolt8 mounted in a rectangular fiat plate 9 mounted on one side of the bracket '3, Figs. 2, 1,5, 6 and 8. The bolts 8 extend respectively through plates 10 fastened to the bracket 3.

Oscillativein a circular recessprovided in the plate 9 between the fulcrarollers 6 is a circular cam member 11 provided with two cams comprising rollers 12 respectively rotatable on shouldered bolts eccentrically mounted in the outer face of the cam member 11 said bolts beng indicated by 13, Figs, 2, 1 and 8.

The cam member 11 is oscillatable between an initial bar receiving position, Fig. 2 and a bar bending position, Fig. 8.

The cam rollers 12 are each provided with oppositely disposed segmental peripheral flanges 14.

he initial position, shown in Fig. 2, after the insertion of the flat bar 4, which is to be bent, in the direction indicated by the curved arrow in Fig. 2 the roller cams 12 will engage opposite edges of the bar 4 and force the bar against the fulcra rollers 6, thus bending the bar 4 into an S bend 5, as shown in F1 8.

The flanges 14 will engage the side 0 the bar 4 distant from the cam member 11, thus preventing the bar from buckling or crim ing during the bending operation. T e flanges 7 of the fulcra rollers 6 also engage the same side of the bar, as the flanges 14, and also prevent buckling of the bar.

For oscillating the cam member 11, the following described mechanism is provided.

The cam member 11 is provided with an axial extension 15 which extends through a hole provided in the bracket 3, and to such extension is fastened, as by a pin 16, a rigid arm 17, which is mounted in a recess 18 in the outer side of a plate 19, Figs. 1, 3, 4, and 5 to 10.

'The arm 17 is pivotally engaged by the plate 19, so that the latter is adapted for circumferential adjustment relative to the arm 17 and the body of the cam' member 11.

To hold the plate 19 in the position to which it is adjusted, two set screws 20 are oppositely disposed in the plate 19 at opposite sides of the recess 18, and are adapted to respectively bear against the opposite sides of the arm 17.

Rotatably mounted in one side of the box 1 is a horizontal driven shaft 21, Fig. 1 which has fastened to it outside the box 1 a crank 22 which is ivoted to a link 23, the latter being pivoted to the plate 19, Figs. 1 and 3.

The plate 19 and arm 17 form a crank in connection with the set screws 20, by which the link 23 oscillated by the crank 22, in turn oscillates the cam member 11 between the initial position and the bending position of the latter.

The adjustment screws 20, and the construction of the cam member crank, as described, are for the purpose of enabling the cam member operating on widths of materialslightly different, and to enable the apparatus to be adjusted so as to obtain just the angle of bends desired in the bar to be bent By adjustment of the set screws 20, the raageof oscillation of the cam member 11 may be changed as to position. but not as to length of oscillation of consequence.

' Any suitable means may be provided for rotating the driven shaft 21. In the drawings there is shown for this purpose a driving pulley 24 fastened to a shaft 25 rotatable in the box walls 1 and having secured to it a pinion 26 which meshes with a gear wheel 27 fastened on a shaft 28 rotatable in the walls of the box 1 and having fastened on it a pinion 29 which meshes with a gear wheel 30 fastened on a horizontal shaft 31 rotatably mounted in the box 1, Fig. 1.

A clutch of any suitable design and designated in Fig. 1 by 32 is adapted to drivingly engage the shaft 31 with the shaft 21 having the crank 22.

The clutch may be operated by any suitable means, as by a rock shaft 33 oscillat-ive in the walls of the box 1 and provided with a crank 34 engaging the clutch mechanism, and having also a crank 35 connected by a link 36 to a vertically depressible treadle 37 pivoted to the box 1 and normally lifted to the clutch disengaging position by a coil spring 38 fastened at its upper end to the box 1 and at its lower end to the treadle.

In the operation of the machine, the parts being as shown in Fig. 2, the operator places a bar 4 in the operative position between the fulcra rollers 6 and the cam rollers 12. He then depresses the treadle 37, thus causing the rotating shaft 31 to drive the shaft 21 through the clutch mechanism 32.

The shaft 21 will revolve a complete revolution, the operator removing his foot from the treadle after having depressed it to engage the clutch with the shaft 21. The shaft crank 22 on revolving a revolution will oscillate the crank plate 19, and with it the set screws 20, arm 17 and cam member 11 in the manner already described, thus causing the cam rollers 12 and fulcra rollers 6 to make an S bend 5 in the bar 4.

Upon the return of the cam member 11 to its initial position, the bent bar 4 may be removed and another substituted for it, and the operation then re eated.

The crank 22 is shorter t ian the cam crank plate 19 and its pivotal connection with the link 23 is at a less distance from the axis of the shaft 21, than the distance of the piv'otal point of the link with the plate 19 is from the axis of. the cam member 11. This construction enables the rotation of the shaft 21 to oscillate the cam member 11.

As shown in Figs. 2 and 8, a stop age plate 39 is attached to the lower end 0 the plate 9 against which the lower end of the bar 4 may be projected, when the bar is inserted between the cam rollers 12 prior to the bending of the bar, so that the S bend in the bar will be made at the proper distance from the adjacent end of the bar.

I do not limit my invention to the structure shown and described, as many modifications, within the scope of the appended claims, may be made without departing from the spirit of my invention.

' \Vhat I claim is:-

1. In a bar bending machine, a support having two fulcra adapted to respectively engage opposite edges of a bar to be bent, a cam member oscillative on said support between said fulcra and having two cams adapted to respectively engage said edges of said bar, a.

rotary shaft, and means connecting said shaft and said cam member by which, upon each rotation of said shaft, said cam member will be turned, first, in a direction such that said cams will force said bar against said fulcra to form an S bend in the bar, and then in the V opposite direction to its initial position.

L'ai

2. In a bar bending machine, a support having two fulcra adapted to respectively engage opposite edges of a bar to be bent, a cam member oscillative on said support between said fulcra and. having two cams adapted to respectively engage said edges of said bar, a retary shaft having a crank, said cam member having a crank which is longer than the shaft crank, and a link connecting said cranks, whereby, upon each rotation of said shaft, said cam member will be turned, first, in a direction such that said cams will force said bar against said fulcra to form an S bend in the bar, and then in the opposite direction to its initial position.

3. In a bar bending machine, a support having two fulcra adapted to engage respectively opposite edges of a bar to be bent, a cam member oscillative on said support between said fulcra and having two cams adapted to respectively engage said edges of said bar and adapted, when said cam member is turned from an initial position in one direction, to force said bar against said fulcra to form an S bend in the bar, each of said cams having oppositely extending segmental peripheral flanges adapted, when said cam member is turned in said direction, to overlap and engage the side of the bar distant from said cam member, and means for turning said member to and from said initial position.

4. In a bar bending machine, a support having two fulcra adapted to respectively engage opposite edges of a bar to be bent, a cam member oscillative on said support between said fulcra and between an initial bar receiving position and a bar bending position and having two cams adapted to respectively engage said edges of said bar and adapted. when said cam member is turned from said initial position to said bending position, to force said bar against said fulcra to form an S bend in the bar, each of said cams having a peripheral segmental flange adapted, when said cam member is turned from said initial position to said bending position, to overlap and engage the side of the bar distant from said cam member, and means for oscillating said cam member between said positions.

5. In a bar bending machine, a support having two fulcra adapted to respectively enopposite edges of a bar to be bent, a cam member oscillative on said support between said fulcra and between an initial bar receiving position and a bar bending position and having two cams rotative thereon adapted to respectively engage said edges of said bar and I cam member having a crank pivotally adapted, when said cam member is turned. from said initial position to said bending position, to force said bar against said fulcra to form an S bend in the bar, each of said cams having a peripheral segmental flange adapted,when said cam member is turned from said init al position to said bending position, to overlap and engage the side of the bar distant from said cam member, and means for oscillating said cam member between said positions.

6. In a bar bending machine, a support having two tulcra adapted to respectively engage opposite edges of afbar to be bent, a cam member oscillative on said support between said fulcra and between an initial bar receiving position and a bar bending position and having two cams adapted to respectively engage said edges oi said bar and adapt-ed, when said member is turned from said initial position to said bending position, to force said bar against i ulcra to form an S bend in said bar, said cam member having a crank circumierentially adjustable relatively to the body of said cam member, and means engaging said crank for oscillating said cam member.

T. In a bar bending machine, a support having two fulcra adapted to respectively engage opposite edges of a bar to be bent, a cam member oscillative on said support between said fulcra and between an initial bar receiv ing position and a bar bending position and having two cams adapt-cc to respectively en gage said edges of said bar and adaptd, when said cam member is turned from said initial position to said bending position, to force said bar against said tulcra to form an S bend in said bar, said cani member having a portion rigid with the body of said cam member, the

engaging said rigid portion so as to have circumferential adjustment relatively thereto, said crank having adjustable means engaging said rigid portion for holding said crank in the position to which it is adjusted, and means engaging said crank for oscillating the same.

8. In a bar bending machine, a support having two fulcia adapted to respectively engage opposite edges of a bar to be bent, a cam member oscillative between said'iulc'ra and between an initial bar receiving position and a bar bending position and having two cams adapted to respectively engage said edges of said bar and adapted, when said cam member is turned from said initial position to said bending position, to force said bar against said fulcra to form an S bend in the bar, said cam member having a rigid radial arm and a crank comprising a radial plate pivotally engaging said arm so as to be circumferentially adjustable relatively thereto and having two oppositely engaged set screws respectively engaging opposite sides of said arm for holding said plate releasably in the position to which it may be adjusted, and means engaging said plate for oscillating the latter and with it said cam member.

9. In. a bar bending machine, a support leaving two fulcra adapted to respectively engage opposite edges of a bar to be bent, a

' cam member oscillative between said fulcra 6&1

and between an initial bar receiving position and a bar bending position and having two cams adapted to respectively engage said edges of said bar and adapted, when said cam member is turned from said initial position to said bending position, to 'force said bar against said fulcra to form an S bend in said bar, said cam member having a crank circumferentially adjustable relatively to the body of said cam member, a rotary shaft having a crank, and a link pivoted to the shaft crank and pivoted to said cam member crank at a radial distance greater than the distance from the axis of said shaft to the pivotal point of the link with said shaft crank, whereby, upon each rotation of said shaft, said cam member is oscillated.

10. In a bar bending machine, a support having two fulcra adapted to respectively engage opposite edges of a bar to be bent, a cam member oscillative between said fulcra and between an initial bar receiving position and a bar bending position and having two cams adapted to respectively engage said edges of said bar and adapted, when said cam member is turned from said initial position to said bending position, to force said bar against said fulcra to form an S bend in said bar, said cam member having a rigid radial arm and a crank comprising a plate pivotally engaging said arm so as to be circumferentially adjustable relatively thereto and having two oppositely disposed set screws respectively engaging opposite sides of said arm for holding said plate in the position to which it may be adjusted, a rotary shaft having a crank, and a link pivoted to said plate and said shaftcrank and pivoted to said plate at a distance from the axis of said cam member greater than the distance between the axis of said shaft and the pivotal point of said link with said shaft crank, whereby, on each rotation of said shaft, said cam member is oscillated.

In testimony whereof I have signed my name to this specification.

WILLIAM S. BROWN. 

